DBT-RISE-TGC/riscv/gen_input/RV64M.core_desc

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import "RV64IBase.core_desc"
InsructionSet RV64M extends RV64IBase {
instructions{
MULW{
encoding: b0000001 | rs2[4:0] | rs1[4:0] | b000 | rd[4:0] | b0111011;
args_disass:"{name(rd)}, {name(rs1)}, {name(rs2)}";
if(rd != 0){
X[rd]<= sext(X[rs1]{32} * X[rs2]{32});
}
}
DIVW {
encoding: b0000001 | rs2[4:0] | rs1[4:0] | b100 | rd[4:0] | b0111011;
args_disass:"{name(rd)}, {name(rs1)}, {name(rs2)}";
if(rd != 0){
if(X[rs2]!=0){
val M1[32] <= -1;
val ONE[32] <= 1;
val MMIN[32] <= ONE<<31;
if(X[rs1]{32}==MMIN && X[rs2]{32}==M1)
X[rd] <= -1<<31;
else
X[rd] <= sext(X[rs1]{32}s / X[rs2]{32}s);
}else
X[rd] <= -1;
}
}
DIVUW {
encoding: b0000001 | rs2[4:0] | rs1[4:0] | b101 | rd[4:0] | b0111011;
args_disass:"{name(rd)}, {name(rs1)}, {name(rs2)}";
if(rd != 0){
if(X[rs2]{32}!=0)
X[rd] <= sext(X[rs1]{32} / X[rs2]{32});
else
X[rd] <= -1;
}
}
REMW {
encoding: b0000001 | rs2[4:0] | rs1[4:0] | b110 | rd[4:0] | b0111011;
args_disass:"{name(rd)}, {name(rs1)}, {name(rs2)}";
if(rd != 0){
if(X[rs2]!=0) {
val M1[32] <= -1; // constant -1
val ONE[32] <= 1;
val MMIN[32] <= ONE<<31; // -2^(XLEN-1)
if(X[rs1]{32}==MMIN && X[rs2]==M1)
X[rd] <= 0;
else
X[rd] <= sext(X[rs1]{32}s % X[rs2]{32}s);
} else
X[rd] <= sext(X[rs1]{32});
}
}
REMUW {
encoding: b0000001 | rs2[4:0] | rs1[4:0] | b111 | rd[4:0] | b0111011;
args_disass:"{name(rd)}, {name(rs1)}, {name(rs2)}";
if(rd != 0){
if(X[rs2]{32}!=0)
X[rd] <= sext(X[rs1]{32} % X[rs2]{32});
else
X[rd] <= sext(X[rs1]{32});
}
}
}
}